From 62534f5df859fc8dbcff925ed2d56a5c74a31b03 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Piotr=20B=C5=82a=C5=BCejewicz=20=28Peter=20Blazejewicz=29?=
 <peterblazejewicz@users.noreply.github.com>
Date: Sun, 3 Nov 2019 11:27:11 +0100
Subject: [PATCH] Add support for keyboard navigation for submenu item

This changes minor details in the BlazoredSubMenu implemenation to
support:
- keyboard based navigation (role and tabindex)
- keyboard based interaction (Enter key down)

Thanks!
---
 src/Blazored.Menu/BlazoredSubMenu.razor    |  4 ++--
 src/Blazored.Menu/BlazoredSubMenu.razor.cs | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/Blazored.Menu/BlazoredSubMenu.razor b/src/Blazored.Menu/BlazoredSubMenu.razor
index 3c6da4b..0a0473c 100644
--- a/src/Blazored.Menu/BlazoredSubMenu.razor
+++ b/src/Blazored.Menu/BlazoredSubMenu.razor
@@ -4,11 +4,11 @@
     <li class="@CssString" disabled="@(!IsEnabled)">
         @if (HeaderTemplate != null)
         {
-            <span @onclick="ToggleSubMenu">@HeaderTemplate <i>@Icon</i></span>
+            <span role="button" tabindex="0" @onclick="ToggleSubMenu" @onkeydown="KeyDownHandler">@HeaderTemplate <i>@Icon</i></span>
         }
         else
         {
-            <span @onclick="ToggleSubMenu">@Header <i>@Icon</i></span>
+            <span role="button" tabindex="0" @onclick="ToggleSubMenu" @onkeydown="KeyDownHandler">@Header <i>@Icon</i></span>
         }
 
         <ul class="blazored-sub-menu">
diff --git a/src/Blazored.Menu/BlazoredSubMenu.razor.cs b/src/Blazored.Menu/BlazoredSubMenu.razor.cs
index 411adb3..13cdf17 100644
--- a/src/Blazored.Menu/BlazoredSubMenu.razor.cs
+++ b/src/Blazored.Menu/BlazoredSubMenu.razor.cs
@@ -1,4 +1,5 @@
 using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.Web;
 using System.Collections.Generic;
 
 namespace Blazored.Menu
@@ -34,5 +35,18 @@ protected void ToggleSubMenu()
             IsOpen = !IsOpen;
             Icon = IsOpen ? "-" : "+";
         }
+
+        /// <summary>
+        /// Handler for the key down events
+        /// </summary>
+        /// <param name="eventArgs">keyboard event</param>
+        protected void KeyDownHandler(KeyboardEventArgs eventArgs)
+        {
+            if (eventArgs.Key == "Enter" || eventArgs.Key == " " || eventArgs.Key == "Spacebar")
+            {
+                ToggleSubMenu();
+            }
+        }
+
     }
 }